While mark sensing systems are known for purposes such as identifying, sorting, and obtaining information from articles ranging from checks to railway cars, and some have enjoyed commercial use, difficulties have been encountered in some instances which the present invention seeks to overcome.
The present invention, though useable in a variety of applications, was particularly developed for identification and sorting of articles, such as vials, bottles, cartons, and the like as in pharmaceutical manufacturing environment, particularly to enable automatic separation of mislabeled articles from a rapidly moving article stream under production conditions.
Proposed systems for this purpose have not been fully satisfactory. One approach marked article labels with invisible codes, for example in magnetizable ink on the back of the label. Marks were sensed through the thickness of the label with a magnetic sensor. However, this required very close spacing of the label marking and sensing device, a condition frequently not achievable on practical article conveying lines. Other known approaches printed codes of various configurations on labels or articles and optically read same. Difficulties included the need for unrealistically high accuracy in printing the code on the label or article, precise control of interplacement and orientation of the sensing device and the code marking on the label or article, a large physical code size (particularly difficult with a small article whose label is to include substantial legible printed information, in addition to the bar code, and may have a maximum dimension of only an inch or two), and so forth.
Accordingly, the objects of this invention include provision of:
A bar code and reader system wherein the bar code is compact and self-clocking, has a plurality of contiguous side-by-side data spaces, and permits data bars forming the coded information to lie in either contiguous and noncontiguous relation.
A system, as aforesaid, in which the data area of the bar code is subdividable lengthwise of the data spaces to radically increase the number of codeable character combinations and wherein the bar code need occupy only a relatively small portion of the surface or label on even relatively small containers, such as pharmaceutical containers of various kinds.
A system as aforesaid, which permits reading of the bar code on a label or article despite substantial variations in bar code size, the location and orientation of successively presented code bearing labels or articles, camera to article spacing, the speed of movement of bar coded articles with respect to the scanning device and so forth.
A system, as aforesaid, capable of high speed, high redundancy line scanning of a bar code, wherein a given bar code image may be line scanned a thousand or more times, with successive scan lines displaced along the length of the code bars.
A system, as aforesaid, which provides high reliability code reading despite substantial imperfections in printing of a bar code.
A system, as aforesaid, capable of alternatively employing different scanning devices particularly matched to the manner of presentation of coded articles, wherein slow moving, close spaced articles may be scanned by high speed, low persistence television camera, and wherein rapidly moving, widely spaced articles may be scanned by a high persistence, image storing Vidicon in cooperation with a periodically actuated high speed strobe lamp.
A system, as aforesaid, which includes circuitry responsive to scanning of an acquisition bar in the bar code for establishing the time spacing of a series of strobe pulses in each scan of the code, wherein the time spacing of the strobe pulses corresponds to the expected lateral center of each of the series of data spaces in the code, and wherein the successive data spaces are interrogated for presence or absence of a data bar only at very narrow locations therein determined by such strobe pulses.
A system, as aforesaid, which produces strobe pulses in a series of down counting operations interspersed by a substantially instantaneous parallel count shift from storage to counting means.
Apparatus, as aforesaid, in which a relatively simple "good-bad" criterion indicates whether a scanned bar code is a proper one.
A system, as aforesaid, wherein a color CCTV receiver may be used as a system monitor in cooperation with a black and white scanning device, wherein different colors displayed on the monitor portray the instantaneous status of a corresponding plurality of different system parameters, both for purposes of setting up the system and in ongoing system operation.
A system, as aforesaid, capable of reading bar codes with high reliability and controlling acceptance of properly labeled articles or rejection of improperly labeled articles.
Other objects and purposes of this invention will be apparent to persons acquainted with apparatus of this general type upon reading the following specification and inspecting the accompanying drawings.